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Bearing Fault Detection and Classification Using Artificial Neural Networks
No full textBearings are the essential components of modern rotating machines. Bearing faults can cause severe machine damages or even breakdowns.
In recent years, artificial intelligence and deep learning have been successfully applied to fault detection. In this thesis, convolutional neural networks (CNN) are employed for bearing fault detection and classification. Computer simulations results demonstrate that the CNN based approach is advantageous over the conventional regression model, with an overall accuracy of 99.5%
Effects of Experimental Scale on the Adsorption of Two Pharmaceutical Drugs Detected in Municipal Wastewater Effluent
Get PDFPharmaceutical drugs are being produced and consumed in increasing quantities every year and are poorly treated by conventional wastewater treatment processes, leading to increasing detection of such compounds in surface water, groundwater, and municipal drinking water. Soil aquifer treatment (SAT) is a promising method for treating these emerging compounds through combined adsorption and degradation of target compounds in soil. This thesis examines the consistency of results from typical studies like adsorption isotherms and soil columns utilized in analysis of SAT performance, across varying experimental scales. The adsorption behavior of two pharmaceuticals was investigated as a function of experimental scale and soil organic content in adsorbent media. This thesis shows that broad trends in pharmaceutical adsorption are not dependent upon experimental scale. Across adsorption isotherm, bench-scale soil column, and large-scale soil column experiments, adsorption and of both drugs was greater in organic soil than inorganic soil, although dispersive transport may have increased in some experiments. Across all experiments, carbamazepine was adsorbed by soils more than diclofenac. Some inconsistencies were observed across scales between the two organic soils, a mediumorganic and high-organic soil, where adsorption was generally greater in high organic soil, but sometimes observed to be greater in medium organic soil. This may suggest that the decrease of experimental control resulting from increased experimental scale obfuscates more nuanced relationships in SAT experimental conditions. Broad trends in data showing whether or not a soil displayed significant adsorptive behavior and which pharmaceutical was adsorbed more were consistent. However, the degree of partitioning via adsorption varied across scales as experimental control decreased with increasing physical scale
Impact of Sex on Proliferation and Maturation of Primary Isolated Myoblasts
Get PDFPeripheral arterial occlusive disease (PAOD) is caused by the buildup of atherosclerotic plaque causing restriction in blood flow in tissue, known as ischemia. It affects 8 million people in the United States and can hinder daily life through the onset of symptoms such as intermittent claudication and in extreme cases ulcers and gangrene. Surgical revascularization is not accessible to certain patient populations, such those of advanced age, highlighting a need for alternative therapies. For example, naturally occurring bypass arteries, called collateral blood vessels, can remodel and enlarge to bypass the occlusion. This process, known as arteriogenesis, has been studied as a mechanism for alternative therapies. Gene and cell-based therapies, like VEGF and BM-MSCs, were promising in animal models, but unsuccessful in clinical trials. An alternative cell-therapy candidate for enhancing arteriogenesis is myogenic cells such as myoblasts. Myogenic cells are essential in muscular repair, but can also enhance angiogenesis, the process for new capillary growth, which undergoes a similar cascade of events as arteriogenesis. Myogenic cells have been evaluated by our group showing that they enhance collateral capillary arteriogenesis in BALB/C mice and collateral arteriogenesis in C57BL/6 mice with diet induced obesity. However, the cells transplanted were not evaluated to determine their identity in the myogenic differentiation pathway due to a lack of cells. The isolation and culture process of myoblasts is arduous. We utilize basic fibroblastic growth factor (bFGF) and a p38 MAPK inhibitor to minimize maturation in culture, however the cells still mature, which slows their proliferation. Currently, we isolate from 4-8 week-old male mice, but sex and/or age may change the amount of cells produced from each isolation. Other groups found that male myofibers produce more satellite cells (SCs) compared to female myofibers, while other studies indicate no difference. Also, male SCs may differentiate faster than female cells. In this work, we evaluated the differences in proliferation and maturation of SCs based on sex in one age group of mice using our isolation and expansion protocols utilizing bFGF and p38 MAPK inhibitor. We hypothesized that male isolations would produce more myogenic cells, but exhibit increased maturation compared to female isolations. The extensor digitorum longus (EDL) muscle was isolated from male (n=4) and female (n=4) 7 week-old mice then chemically and mechanically digested to isolate individual myofibers for culture. Satellite cells migrate from the myofibers and proliferate and differentiate into myoblasts before maturing into myocytes. Cell counts were extrapolated from daily images of each culture and compared to the hemocytometer counts on days of passage or cryopreservation. Results suggest a trend that female isolations produce more cells compared to male isolations. Comparison of image cell counts to hemocytometer counts show no difference based on sex but suggest that a lower seeding density after passage produces less adherent and mature myogenic cells in culture compared to higher seeding densities. Future work will include investigation of fiber density on production of satellite cells, seeding density on reducing maturation of myogenic cells in culture, and evaluation on how age affects proliferation of the myogenic cells
Leveraging Lessons Learned from a Virtual Hands-on Outreach Program to Cultivate Diversity in the Next Generation of Structural Engineers
Get PDFA challenge that continues to face the structural engineering (SE) profession is the recruitment and retention of individuals from underrepresented minority (URM) groups, underscored over the years by findings reported on by the SE3 project committee. One approach to address this is by developing and conducting early outreach efforts with diverse populations of K-12 students, so they are aware of SE’s meaningful contributions to society and the intriguing technical problem- solving opportunities in this field. During these educational activities it is also important for young students to be exposed to engineering practitioner-educators who represent diverse backgrounds and whose lived experience demonstrates a path forward for URM members in the industry.
This paper focuses on a virtual outreach program offered in Summer 2021, that yields insights about facilitating middle and high school students in a hands-on earthquake engineering project as well as software programming activities. This week- long program was affiliated with the Cal Poly Engineering Possibilities in College (EPIC) summer camp which provides pre-college experiences to students, specifically from underrepresented backgrounds. The instructor team prototyped, manufactured, and shipped over 120 low-cost engineering kits so students could construct a shake table and building model as well as test their baseline and retrofitted designs. These hands-on activities accompanied lectures to help students understand earthquake hazard, seismic design of buildings, instrumentation, and data visualization among other topics.
The curriculum, mail-home engineering kit details, and reflection on student performance will be discussed in the paper to provide readers with a guide for developing meaningful outreach experiences that engage diverse groups of students in exploring SE. The group of all-female instructors will also share their perspective on some potentially effective methods to recruit diverse engineers to participate in outreach: to achieve their aspirations of impact the next generation, cultivate their interest in the SE field, and thus, be motivated to persist and ascend in their careers
Battery Energy Storage System
Get PDFThe Battery Energy Storage System (BESS) project consists of bringing an existing photovoltaic battery energy storage system into service within Cal Poly’s Energy Conversion Lab. Information regarding the BESS is limited to the existing manuals as the original equipment manufacturer has ceased supporting the product in the United States. Results from previous projects on the BESS speculated that a DC input may be required to enable the system’s to be fully operational. The goal of the project is to provide a DC input into BESS and test the system’s functionality. Initially, a Photovoltaic Thevenin Equivalent was expected to be utilized as the DC Input. Cal Poly Professor Dr. Poshtan obtained programmable DC Power Supplies that can also function as a Photovoltaic Emulator when used with the corresponding software. The programmable DC Power Supply was utilized for the DC Input into the BESS. When used as a simple DC supply, the supply provided low current into the BESS. The Power Supply when used as a PV emulator is able to provide more current. The main issue when utilizing the PV emulator connected to the BESS is that the power output would reach the maximum then continuously reset in a loop. It can be concluded that a single PV emulator was unable to provide sufficient power to successfully operate the BESS. It is believed that this looping is due to issues with the inverter’s synchronization with the power grid or a lack of sufficient power in each individual photovoltaic input. Future steps include connecting multiple power supplies to the inverter to explore the possibility of more power for each individual photovoltaic input on the inverter
Case Study on the Reduction of Electrical Packaging to Help with Overall Construction Waste
Get PDFThe construction industry has a significant amount of waste accumulated on every job site. This study utilizes research on the types of materials that make up waste and the waste management strategies behind it. Waste materials range from building materials, such as lumber and steel, to packaging materials, like plastic and cardboard. This paper concentrates on material packaging and discovering ways to eliminate some of the construction waste before materials even arrive on the job site. A case study was performed on electrical lighting fixture packaging to observe and analyze the different amounts of waste accumulated. This examination focused on traditional light fixture packaging compared to the reinvented “Stack Pack” packaging. It was found that Stack Pack packaging is able to carry four times the amount of light fixtures compared to traditional packaging, and both produce a similar amount of waste. This is possible by modifying the original packaging by stacking the product and layering it with a cardboard cushion. This reduction of material is responsible for reducing factors such as time, cost and labor and has the ability to impact the amount of waste in all construction if incorporated in other trades
Associations between Parenting Stress, Parent Feeding Practices, and Perceptions of Child Eating Behaviors during the COVID-19 Pandemic
Get PDFThe aim of this study was to explore associations between parenting stress, feeding practices, and perceptions of children\u27s eating behaviors during the COVID-19 pandemic. Parents (n = 284) of children ages 4–6 years completed a cross-sectional online survey during the onset of pandemic-related stay-at-home mandates in the U.S. Parents reported current levels of parenting stress, feeding practices, and child eating behaviors. Parents also reported whether parenting stress had increased, stayed the same, or decreased since prior to the onset of pandemic-related stay-at-home mandates. Greater levels of parenting stress were associated with less desirable feeding practices, including greater odds of high use of food for emotional regulation (OR = 1.05, 95% CI = 1.03–1.08), food as a reward (OR = 1.05, 95% CI = 1.02–1.08), and pressure to eat (OR = 1.03, 95% CI = 1.01–1.06), and low use of encouraging a balanced diet (OR = 1.03, 95% CI = 1.01–1.06). Greater levels of parenting stress were also associated with greater perceptions that children exhibited problematic eating behaviors, including greater odds of high food fussiness (OR = 1.05, 95% CI = 1.02–1.08) and low enjoyment of food (OR = 1.05, 95% CI = 1.02–1.07). For parents who reported their parenting stress had increased, greater parenting stress was associated with more frequent use of pressure to eat (p = .009) and less frequent monitoring their child\u27s diet (p = .028). In conclusion, parenting stress during the pandemic was associated with use of food for emotional and behavioral regulation and perceptions that children exhibited problematic eating behaviors. Further research is needed to understand how to mitigate parenting stress and promote healthy feeding practices during times of crisis
The Design, Construction and Analysis of a Large Round Bale Handling Implement
Get PDFTo entice a small-scale hay producer to purchase equipment that will improve their hay hauling operation, a more cost effective and more universal solution must be developed. The objectives of this project are to develop and test a prototype large round bale handler. The prototype was built to industry standards, using modern electronic controls and the latest design and fabrication methods. The prototype makes use of an existing trailer and by doing so can be a less expensive method of hauling hay when compared to other equipment currently on the market. While the combination of the prototype bale handler and new equipment trailer is similar in price to a stand alone round bale handler, a small-scale hay producer might be more likely to purchase the combination of the bale handler and trailer because the trailer can be used for many tasks throughout the year